The present invention relates to a sampling tube for obtaining molten metal samples.
In the determination of the content of the molten metal, such as during steel manufacturing process, it is desirable to monitor the content of the melt during various stages of production. A variety of sampling devices have been suggested, particularly for use with specimen gases such as hydrogen, which is particularly difficult to sample and determine inasmuch as gaseous hydrogen can easily escape while residual hydrogen remains in the solid specimen removed by the sampling device. U.S. Pat. No. 4,445,390 discloses a sampling device for the removal of a sample from a molten metal bath to capture the total hydrogen content of a sample. In this and other evacuated tube samplers, however, the molten metal bonds to the wall surfaces of the sampler, and when the solid sample is analyzed therefore, the resultant pin sample includes not only the molten metal desired to be sampled but a section of the sampling device itself. Although the weight and impurities, if any, in the sampling tube can be compensated for, by estimation, but the results are not as accurate as obtainable with the sampling device of the present invention which allows the actual weight of the pin sample to be determined.